OCI callbacks and C++

Anyone have any ideas/insights/suggestions/etc about handling OCI callbacks from a
C++ program on Solaris?

Specifically, handling a RETURNING INTO clause with OCIBindDynamic().

The compiler is unhappy unless the callbacks are outside of the class definition, declared
as 'extern "C" sb4'

I'm trying to figure out the best way to get the data back and forth between the callbacks
and the statement objects.

Thanks.

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